Tentering and drying machine



Feb, 25, 1936., HA I 2,032,0 14

TENTERING AND DRYING MACHINE Filed Jan. 15, 1952 2 Sheets-Sheet l Feb. 2 5, 193%. v M AHN 2,032,014

' 'TENTERING AND DRYING MACHINE.

Filed Jan. 15, 193 2 Sheets-Sheet 2 Patented Feb. 25, 1936 PATENT OFFICE TENTERING DRYING MACHINE Mathias Hahn, Aachen, Germany, assignor to H. Krantz Siihne, Aachen, Germany Application January 15, 1932, Serial No.- 586,839 In Germany January 17, 1931 1 Claim. (01. 34-48) This invention relates to multi-tier tentering and drying machines of the so-called cross-current type, that is to say to machines in which the drying air is passed or circulated through the machine transversely to the direction of travel of the fabric.

The invention has for its object to so improve the machines of the kind stated that the area I of fabric surface treated at a time in a machine of predetermined length and height is considerably increased, for instance doubled, whereby there is attained a corresponding increase of the output without increasing the expenditure of power required for the circulation of the air. This object is realized by arranging the fabric reversing drums, which are located at the front and rear end or at the top and bottom of the machine, so close to each other that the average space between the several fabric layers is materially reduced, for instance to about half the diameter of a reversing drum.

In tentering and drying machines working with longitudinal air currents, it has already been proposed to pass the fabric through the machines in relatively close layers by mounting the reversing drums close to each other or by providing particularly arranged chain guides. Now, it is a recognized fact that longitudinal-current machines of normal construction even, which means machines in which the space between the fabric layers corresponds to the diameter of the reversing drums, have an output which amounts only to about half the output of a normal cross-current machine, this being due to the minor area of cross-section at disposal for the passage of the air in longitudinal-current machines. Guiding the fabric in these machines in relatively close layers therefore is and has proved to be a failure. By such close guiding of the fabric the section at dis- 4 posal for the introduction and discharge of the air is still further reduced, air can only be blown into some of the spaces between the fabric layers and eventually the flow of the air is impeded by the fabric layers which run at an in- 45 cline in the longitudinal direction of the machine. In these machines, the advantage of the increase of the amount of fabric adapted to be treated at a time is therefore compensated or outweighed by the disadvantage of the consid- 50 erable reduction of the amount of air adapted to be circulated through the machine.

In cross-current machines the conditions are greatly difierent from those in longitudinal-current machines. In such machines, the total 5 length and height of the machine-less the thickness of the fabric layers-is at disposal for the passage of the air so that large quantities of air can-be circulated in such machines. By increasing. for example doubling the number of fabric layers, the section at disposal for the passage of the air is only reduced by the thickness of the additional fabric layers, an amount which is practically insignificant. It is not necessary to increase the power required for the circulation of the air. It is exactly by the close arrangement of the fabric reversing drums that the large quantities of air adapted to be circulated in crosscurrent machines can be fully utilized with the result that the drying efiiciency is considerably increased, for instance doubled. At the same time the consumption of heat per unit of output is reduced and the number of drying tiers increased.

In the drawings,

Fig. 1 is a longitudinal section of an embodiment of a cross-current machine according to 20 the invention and Figs. 2 and 3 are a cross-section and a horizontal section, respectively, of this machine.

Referring to the drawings, and more particularly to Figs. 1, 2 and 3, the numeral l designates 25 the enclosure in which the fabric F is treated, the fabric entering the enclosure at A and leaving it B. The fabric is conveyed to and fro through the machine by means of chains '2 running in guide rails 3 and two series of drums 30 4, 6, 8, l0, l2, l4 and 5, l, 9, ll, l3, I5 arranged in superposed relation at opposite ends of the enclosure l and designed to reverse the fabric at these ends. I6 are fans for circulating the air through the enclosure substantially transversely to the direction of travel of the fabric F. I! are radiators for heating the air passed through the machine. I8 is a fan for drawing off the saturated exhaust air. The flow of the air is clearly indicated by arrows in Figs. 2 and 3.

The dimensions of the machine and the diameters of the reversing drums are the same as in the known machine. The reversing drums are, however, arranged close to each other so that each fabric layer runs onto a reversing drum closely below the layer which runs 01f the next higher reversing drum. By'virtue of this arrangement the machine shown in Figs. 1, 2 and 3 can hold twelve fabric layers I9, 20, 2|, 22, 23, 24, 25, 26, 21, 28, 29 and 30. The increase of the resistance to the air is therefore practically nil.

It will be clear from the drawings, that for guiding the fabric in accordance with the present invention it suffices to arrange the chain guide rails 3 wholly or partly at a proper inclination, no intermediate guide rolls or the like being required.

The invention is not only applicable to machines in which the fabric layers run substantially horizontally but also to machines with vertically running layers. In the latter case, the reversing drums'are not disposed one above the other at the ends but side by side at the top and bottom of the machine. The drying tiers are then also side by side and not above each other. f'he fabric may also be fed to the machine at the bottom and delivered therefrom at the top instead of being fed at the top and delivered at the bottom, as shown.

Having thus describedmy invention, what I claim as new and desire to secure by Letters Patent is:- I 4 In a tentering anddrying machine of the type including an enclosure, means for guiding the fabric to and fro through the enclosure on a circuitous path in spaced layers forming successive drying tiers open throughout substantially the length and height of the enclosure, said means including rotating reversing drums at opposite sides of the enclosure, guide rails, chains running in guide rails and over the drums, means for connecting the fabric to the chains, and means for passing air through the respective drying tiers in a direction substantially transverse the direction of travel of the fabric, the reversing drums at each end of the enclosure being of a size to provide proper travel of the chains thereover and arranged relatively close to each other, with their relative spacing maintaining the fabric layers sufficiently close together as to utilize substantially the full volume of drying air passing therebetween for drying purposes to thereby avoid the necessity of projecting a large volume of air transverse the layers; the intermediate portion of which large volume of air is normally without drying effect on the fabric, certain of the guiding rails being in part inclined to permit the fabric layers to be substantially parallel throughout their greater length of travel lengthwise the machine.

MATHIAS HAHN. 

